Letters seeking details of what measures have been taken to implement a 2000 EU directive on equality in employment have recently been sent to all of the Union's governments, sources close to Vladimir Spidla, the commissioner for employment and social affairs, have confirmed.

The law forbids discrimination in the workplace on grounds of race, ethnic origin, religion, sexual orientation or disability.

Spidla has said that the Commission will start legal proceedings against any government which is not implementing the directive correctly. The deadline for transcribing the directive onto the national statute books was December 2003 for the 15 'old' member states, while the ten newer entrants had to have it transposed by the time they joined the EU in May 2004.

Homosexuality in the workplace was a controversial topic during elections in Poland last year. The right-wing Law and Justice Party, which won the biggest single bloc of seats in the Sejm, the national parliament, advocated that gay men should be banned from teaching. The party leader Lech Kaczynski, the victor in a run-off for Poland's presidency in late October, had banned a gay pride parade while mayor of Warsaw just a few months earlier.

Last month Spidla said that any moves to dismiss teachers "purely on the grounds of their sexual orientation would in principle be considered discriminatory under the directive". He was replying to a query from Jonas Sjöstedt, an MEP for Sweden's Left Party.

Sjöstedt said that he was perturbed by efforts to ban gay and lesbian marches in Poland and Latvia. Although a ban on the first Gay Pride celebration in Riga was overturned following a court ruling in July, the Latvian Prime Minister Aigar Kalvitis said that it was unacceptable for "sexual minorities to parade in the very heart of Riga, next to the Doma church".

"I would consider gay rights to be among the most fundamental of rights," Sjöstedt added. "If some member states don't accept fundamental rights, then the Commission should intervene."

In Poland a gay teacher in Plock, a city 100 kilometres north-west of Warsaw, is currently challenging his dismissal.

Robert Bietro, a spokesman for Poland's Campaign Against Homophobia, said: "We have only one case like this. The reality is that homosexuality is a taboo and that gay people don't want to come out because they are afraid they will lose their jobs. The government claims that there is no homophobia in the workplace but that is completely absurd."

But a Polish diplomat insisted that school authorities were not allowed under national law to inquire into the religious belief or sexual orientation of any teacher.

"Some opinions were expressed on these matters during the election campaign," the diplomat added. "But, frankly speaking, nobody took them seriously."